I've been using google inbox for 2 years now since it was first released and for me its the best email app(service) from google. I always recommend it to my friends and they always tell me you're right. If you use Gmail, Inbox is a must have because it will make your Gmail more organized and productive.
Here's what I like the most about Google Inbox.
1. Bundles your email according to types. for example, all your finances email like email from banks will be bundled under Finance. All the confirmation email from the online stores will be under Purchases. Inbox will automatically bundles it for you.
2. Swipe right to mark an email done. once marked done email be archived so the only thing you will see on the main screen are the emails you havent read yet or emails that are important to you.
3. Pinned Email and Reminders. For example you received an email about your credit card bill. You can tell inbox to remind you about that. you can also pin an email that you want to see always on the main screen.
4. It works on iOS, Android and the web. Just go the app store or playstore to download the app or just go to https://inbox.google.com to use google inbox right away.
that are just the few things Google Inbox can do for you. To know more about google's inbox, watch the video google made about Google's Inbox or click this https://www.google.com/inbox/. Thanks.